Inelastic collisions in radiofrequency-dressed mixtures of ultracold atoms

Abstract

Radiofrequency (rf)-dressed potentials are a promising technique for manipulating atomic mixtures, but so far little work has been undertaken to understand the collisions of atoms held within these traps. In this paper, we dress a mixture of Rb85 and Rb87 with rf radiation, characterize the inelastic loss that occurs, and demonstrate species-selective manipulations. Our measurements show the loss is caused by two-body Rb87+Rb85 collisions, and we show the inelastic rate coefficient varies with detuning from the rf resonance. We explain our observations using quantum scattering calculations, which give reasonable agreement with the measurements. The calculations consider magnetic fields both perpendicular to the plane of rf polarization and tilted with respect to it. Our findings have important consequences for future experiments that dress mixtures with rf fields.